From the looks of the files in SimPE... it kinda looks like that the package files for the dress recolors came straight from the "Projects" folder instead of being copies of the imported versions from the "Saved Sims" folder. The package files in the project folders do absolutely nothing in-game, so that might be what's going on with the recolors. It's the newly created files in the Saved Sims folder that are needed in order for the wedding dress recolors to show.

(Just my guess, because normally re-imported Bodyshop recolors have a "Binary Index" and "Text List", the description line for the thumbnails, that goes with them. None of the recolors have those lines in SimPE. Feel free to correct me if I'm mistaken. :slap: )